Spring actuated key for typewriters



Jully 24, 11934, e. w. MUNSON ET AL.

SPRING ACTUATED KEY FOR TYPEWRITERS Filed May 12, 1955 WNVENTORS ATTORNEYS Patented July 24, 1934 T'A'rss P AT ENT 0 FFI SPRING ACTUATED KEY FOR TYPE- WRITERS tion of New York Application May 12, 1933, Serial No. 670,708

5 Claims.

This invention relates to improvements in spring actuated keys for typewriters adapted to be fitted to the of typewriting machines or other similar key operated machines.

One object of the invention is to provide a spring actuated key which is simple in construc tion, eificient in operation, and economical to manufacture.

Another object of the invention is to provide a very compact key, the upper member of which is yieldingly supported to telescopically slide within the lower member and provided with means for preventing its rotation in the lower member.

Another object is to provide certain improvements in the form, construction and arrangement of the several parts whereby the above named and other objects may efiectively be attained.

A practical embodiment of our invention is represented in the accompanying drawing, in which Fig. 1 represents a plan view of our improved key attached to a typewriter key button and lever;

Fig. 2 represents a front elevation of the same, partly in section;

Fig. 3 represents a vertical section taken in the plane of the line III-III of Fig. 2, looking in the direction of the arrows;

Fig. 4 represents a horizontal section taken in the plane of the line IVIV of Fig. 2, looking in the direction of the arrows; and

Fig. 5 represents a vertical section, similar to Fig. 3, with the parts in another position.

In the drawing we have shown our improved key applied to the well known key button denoted by 1 fixed on the type lever 2 of a typewriter or other similarly operated machine. The present invention comprises a lower member 3 adapted to be removably secured to the key button 1, an upper member 4 telescopically slidable in the lower member, a helical spring 5 interposed between the upper and lower members, and a cap 6 fixed to the upper member.

The lower member 3 is formed of a single piece of relatively thin sheet metal and developed into a shallow cup 7 having a bottom 8, an inner side wall 9 uprising from the bottom to an inwardly curved rim 10, from which depends an outer wall 11. This wall is extended below the plane of the bottom 8 in position to embrace the side of the key button 1 so that the bottom 8 will rest upon the button. The depending wall 11 of the lower member 3 is crimped at 12 to impinge against the side of the key button 1 and maintain the member in position thereon. The upper member 4 is tubular and also formed of relatively thin sheet metal. The lower end of the member 4 is provided with an outwardly 63 extending flange 13 which is cut away at 14 to form notches, the function of which will be'hereinafter explained. The upper peripheral edge of the tubular member 4 is rolled inwardly and downwardly to form an overhanging annular es recess 15. The lower portion of the upper member 4 is di posed to slide in the shallow cup 7 with its flange 13 in close proximity to'the inner side wall 9 of the cup '7. The rim 10 of the cup 7 iscurved inwardly in position to be engaged by the flange 13 and prevent the member 4 from being unintentionally displaced or removed from the cup 7. The spring 5 is positioned in the cup '7 with one end resting on the bottom 8 and the other end seated in the overhanging annular recess 15 of the upper member 4, so that the spring 5 will normally hold the upper member 4 in its upward or extended position with the flange 13 in engagement with the inwardly curved rim 10 of the cup 7. In order to prevent the member; 4 from rotating in the cup '7, we provide one or more tongues 16, in the present instance two are shown, which are cut from the bottom 8 and bent upwardly adjacent the side wall 9 of the cup 7. The position of each of the tongues 16. 35 is such as to slidably fit in the notches 14 in the annular flange 13 of the member 4, thereby preventing the member from rotating in the cup.

The cap 6, in the present instance, is composed of rubber or other similar material and has its/ crown dished at 17, while its under side is provided with an annular channel 18 and a central cavity 19.

The walls of the annular channel 18 are undercut so that when the cap is positioned Ontthe upper member 4, the peripheral rolled edge of the upper member will be frictionally secured in the channel between the walls and the cap locked against unintentional displacement.

The cap 6 is also provided with a reinforcing; ring 20 of metal or other similar material embedded in the annular wall 21 between the channel 18 and cavity 19, which ring tends to stiffen the inner annular wall of the channel and prevent the unintentional removal of the. cap 6 from the upper member 4.

It will be understood that various changes may be resorted to in the form, construction and arrangement of the several parts without departing from the spirit and scope of our in-,

vention, and hence we do not intend to be limited to the details herein shown and described, except as they may be included in the claims.

What we claim is:

1. A spring actuated key for typewriting machines comprising, a lower member adapted to be fitted to the key button of the machine and provided near its upper end with a bottom integral therewith to form a shallow cup therein, a tubular upper member slidable in said shallow cup and having an inwardly turned upper edge to form an overhanging recess therein, a helical spring disposed in the cup and having one end resting on said bottom and the other end seated in said recess in the upper member, means on the upper member arranged to be engaged by the lower member to limit the upward movement of theupper member, and a cap fixed on the upper open end of the upper member and,

arranged to overlap the inwardly turned upper edge.

2. A spring actuated key for typewriting machines comprising, a lower member adapted to be fitted to the key button of the machine and provided near its upper end with a bottom integral therewith to form a shallow cup therein, a tubular upper member slidable in said shallow cup and having an outwardly extended flange at its lower end and an inwardly and downwardly turned upper edge to form an overhanging recess therein, a helical spring disposed in the cup and having one end resting on said bottom and the other end seated in said recess in the upper member, an inwardly disposed rim on the cup arranged to be engaged by said flange to limit the upward movement of the upper member, and a cap fixed on the upper open end of the upper member and arranged to overlap the inwardly and downwardly turned upper edge.

3. A spring actuated key for typewriting machines comprising, a lower member adapted to be fitted to the key button of the machine, a tubular upper member slidable in said lower member, a spring compressible in and between the members, and a cap having an undercut annular channel in its under side disposed in position to embrace the upper open end of the tubular member for securing the cap thereon.

4. A spring actuated key for typewriting machines comprising, a lower member adapted to be fitted to the key button of the machine, a tubular upper member slidable in said lower member, a spring compressible in and between the members, and a cap having inner and outer annular depending walls forming an undercut annular channel in its under side disposed in 7 nel in its under side disposed in position to embrace the upper open end of the tubular member, said inner wall being inclined outwardly towardthe bottom to project under the inwardly turned upper edge of the upper open end of the tubular member for securing the cap thereon.

GARRY W. MUNSON. EUGENE HEBEL. 

